Test Code TCGRSO T-Cell Receptor Gene Rearrangement, PCR, Blood
Additional Codes
Mayo Test Code: TCGR
Reporting Name
T Cell Receptor Gene Rearrange, BUseful For
Determining whether a T-cell population is polyclonal or monoclonal using blood specimens
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
Whole bloodShipping Instructions
Specimen must arrive within 7 days of collection.
Necessary Information
Include relevant clinical information and cytogenetic results, if available.
Specimen Required
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD)
Specimen Volume: 4 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole blood | Ambient (preferred) | 7 days |
| Refrigerated | 7 days |
Special Instructions
Reference Values
An interpretive report will be provided.
Positive, negative, or indeterminate for a clonal T-cell population
Day(s) Performed
Monday through Friday
Test Classification
This test was developed using an analyte specific reagent. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81340-TCB (T cell antigen receptor, beta) (eg, leukemia and lymphoma), gene rearrangement analysis to detect abnormal clonal population(s); using amplification methodology (eg, PCR)
81342-TCG (T cell receptor, gamma) (eg, leukemia and lymphoma), gene rearrangement analysis, evaluation to detect abnormal clonal population(s)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| TCGR | T Cell Receptor Gene Rearrange, B | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 18210 | Final Diagnosis: | 22637-3 |
| 608951 | Signing Pathologist | 19139-5 |
Cautions
To determine the significance of the result, it must always be interpreted in the context of other clinicopathologic information.
The interpretation of the presence or absence of a predominant T-cell receptor (TCR)-gene rearrangement profile is sometimes subjective.
The detection of a clonal TCR-gene rearrangement by this test is not necessarily synonymous with the presence of a T-cell neoplasm. False-positive results can occur because of the sensitivity of polymerase chain reaction (PCR) technique and the problem of nonuniform (skewed) amplification of target T-cell gene rearrangements. The latter problem can occur when the total T-cell number in a sample is limited or due to physiologic skewing of the T-cell repertoire as seen with aging, post-transplantation, or T-cell reactions in autoimmune or (nonlymphoid) malignancies. False-negative results can occur for many reasons, including tissue sampling, poor amplification, or failure to detect a small minority of T-cell gene segment rearrangements with the use of consensus PCR primers. In some cases, an indeterminate or equivocal result will occur because the pattern of gene rearrangements is abnormal (compared to typical polyclonal T-cell processes), but not definitive, for a monoclonal T-cell population. In these situations, distinction of a small monoclonal subpopulation from an over-represented, but reactive, population may not be possible.
Report Available
5 to 10 daysSpecimen Retention Time
Whole blood: 2 weeks; Extracted DNA: 3 monthsReject Due To
| Gross hemolysis | Reject |
| Moderately to severely clotted | Reject |
Method Name
Polymerase Chain Reaction (PCR)
Forms
1. Hematopathology Patient Information (T676)
2. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.